The biggest whooping cough outbreak for several decades is sweeping across the US. In relation to this researchers have zeroed in on the main cause: the safer vaccine that was introduced in the 1990s loses effectiveness much faster than previously thought. This has come from a study published in the New England Journal of Medicine.
The study found that the protective effect weakens dramatically soon after a youngster gets the last of the five recommended shots around age 6. Furthermore, the protection rate falls from about 95 percent to 71 percent within five years, said researchers at the Kaiser Permanente Vaccine Research Center in Oakland, California.
In light of the findings, health officials are considering recommending another booster shot for children, strengthening the vaccine or devising a brand new one.
Whooping cough, or pertussis, is a highly contagious bacterial disease that can strike people of any age but is most dangerous to children. Its name comes from the sound youngsters make as they gasp for breath.
For more on this issue see CBC News.